Method and apparatus for predicting noise within of motor vehicles

摘要

PROBLEM TO BE SOLVED: To simplify estimation of load noises. ;SOLUTION: Tools 14A are sequentially mounted to four wheels, each of them is independently struck in cross three-axis directions by an impulse hammer 14B, and at the same time the sound pressure of noises being produced with vibration force due to the strike is measured by a microphone 16 in a vehicle. In an FFT analyzer 18A, a frequency response function from the vibration force to the sound pressure of the noises is calculated. In a drum tester 24, a tire 26 is mounted to an axis and is rotated and the axial force in the cross three-axis directions is measured by a load cell 28. An axis signal is inputted to the input channel of a FFT analyzer 18B and the auto power spectrum of the axial force in the cross three-axis directions and the cross power spectrum between different two-axis directions are calculated. A computer 20 synthesizes, for four axes, the frequency response function of the four standard wheels and the auto power spectrum and cross power spectrum of the tires whose noise is to be predicted, and calculates the power spectrum of the load noise.;COPYRIGHT: (C)1999,JPO